Download Recommendations and Creating a Systematic Interpretation

2017 Oregon Dental
Conference®
Course Handout
Shawneen Gonzalez, DDS, MS
Course 8110: “CBCT in the Dental Office:
Recommendations and Creating a Systematic
Interpretation”
Thursday, April 6
1:30 pm - 4:30 pm
CBCT in the Dental Office: Recommendations and
Creating a Systematic Interpretation
Objectives
1. Describe the strengths and limitations of CBCT aiding in the prescription and use of CBCT scans
based on academy recommendations.
2. Describe and identify common incidental findings seen on CBCT scans.
3. Create a sample CBCT written interpretation.
ADA Recommendations (August 2012)
Prescribing a CBCT
1. You MUST review the patient’s medical and dental history prior to prescribing a CBCT scan.
2. You MUST perform a thorough clinical examination prior to prescribing a CBCT scan.
3. You MUST show justification that the excess radiation to the patient will result in a benefit
outweighing the risk.
4. CBCT scans SHOULD only be prescribed when traditional (2D) radiographs will not show the area in
question.
5. CBCT scans SHOULD be prescribed by a licensed dentist with training and education in CBCT imaging.
This includes staying informed with evidence based articles and continuing education courses on the use
of CBCT in dentistry.
Taking a CBCT scan (for offices with a CBCT machine)
1. Before a CBCT machine is installed, a health physicist SHOULD be consulted to ensure the machine is
placed in an area that abides by federal regulations, state regulations and National Council on Radiation
Protection & Measurements (NCRP) report 145.
2. ALARA (as low as reasonably achievable) SHOULD always be used. This means using the smallest FOV
(field of view) with the shortest exposure time that will show the area in question.
3. Thyroid collars and lead aprons SHOULD be used as long as they do not interfere with the area being
scanned.
4. Dental professionals using a CBCT scan MUST receive training and education about the safe use of a
CBCT machine.
5. Offices with a CBCT machine SHOULD take continuing education courses on CBCT and radiation
safety.
6. Offices with a CBCT machine MUST follow federal and state radiation regulations. Offices SHOULD
establish a quality control program including having a health physicist evaluate the machine on a set
schedule (typically determined by your state radiation regulations).
Interpretation of a CBCT scan
1. CBCT scans SHOULD be evaluated by a dentist with training and education in CBCT interpretation.
2. The entire CBCT scan (or dataset) MUST be interpreted and findings entered into the patient chart. It
is the responsibility of the referring dentist to relay these findings to the patient.
AAOMR Recommendations (2008)
The American Academy of Oral and Maxillofacial Radiology (AAOMR) has recommendations for dentists
who either have a CBCT unit in their office or those who are referring a patient for a CBCT. The four
recommendations are as follows.
1. The CBCT unit must be operated by either a licensed practitioner or certified radiologic operator.
2. The practitioner, referring or owner, is responsible to interpret the findings of the entire scan and
generate a report of the findings. The scan may be interpreted by an oral and maxillofacial radiologist to
aid the practitioner.
3. Documentation in the patients’ record must show that a clinical exam and history were obtained as
well as demonstrate the need for CBCT.
4. The imaging site should use the lowest radiation dose as necessary to achieve the desired result.
Anatomy and Common Incidental Findings (By Regions)
Paranasal Sinuses
Sinus
Maxillary Sinus
Key Anatomy
Maxilla bone
Other
Infraorbital foramen and canal
Zygomatic process of the maxilla
Uncinate process (part of ostiomeatal unit)
Sphenoid Sinus
Ethmoid bone
Sphenoid bone
Ethmoid Air Cells
Lamina papyracea
Frontal Sinus
Ethmoid bone
Lacrimal bone
Frontal bone
Mastoid Air Cells
Temporal bone
Mastoid process (primarily)
Common Incidental Findings
Finding
Mucous retention
pseudocyst
Views best
visualized on
Radiopaque soft tissue thickening of the sinus to complete Axial
radiopacification of a sinus
Coronal
Sagittal
Dome-shaped radiopaque mass in a sinus
Coronal
Sagittal
Antrolith
Radiopaque entity in a sinus (calcification)
Sinusitis
How it presents
Axial
Coronal
Sagittal
Nasal Cavity
Bones that create this
region
Maxilla
Lateral borders
Forms part of nasolacrimal duct border
Ethmoid
Uncinate process
Uncinate process is part of the ostiomeatal unit
Nasal concha
Superior and middle
Meatus
Superior and middle
Perpendicular
plate
Perpendicular plate is part of the nasal septum
Vomer
Key Anatomy
Other
Vomer is main bony component of the nasal
septum
Palatine
Inferior Nasal Concha
Inferior meatus is drainage for nasolacrimal duct
Nasal
Common Incidental Findings
Finding
Deviated nasal septum
Concha Bullosa
(aerated concha)
How it presents
Deviation of the nasal septum
Views best visualized on
Axial
Coronal
Radiolucent center of a concha
Axial
Coronal
Airway
Airway part
Nasopharynx
Oropharynx
Laryngopharynx
Common Incidental Findings
Finding
Adenoidal hyperplasia
Borders
Soft palate (uvula) superiorly to
posterior border of the nasal
cavity
Soft palate (uvula) inferiorly to
the epiglottis
Other
Adenoids
Tonsils
Epiglottis inferiorly to cricoid
cartilage
How it presents
Enlargement of adenoids in
nasopharynx
Views best visualized on
Sagittal
Cranial Skull Base
Bones that
Key Anatomy
create this
region
Frontal
Ethmoid
Sphenoid
Occipital
Temporal
Cribiform plate
Crista galli
Body
Other
Crista galli is attachment for falx cerebri
Sella turcica, Clinoid processes (anterior and posterior), Clivus, Carotid
sulcus which houses cavernous sinus including internal carotid artery,
foramen lacerum, carotid canal
Greater wings
(2)
Foramen rotundum, foramen ovale, foramen spinosum and vidian canal
Lesser wings
(2)
Lesser wings include optic canal and superior orbital fissure
Pterygoid
processes (2)
Medial and lateral pterygoid plates with hamulus projecting off the medial
pterygoid process.
Also creates borders for pterygomaxillary fissure and pterygopalatine fossa
Posterior to foramen magnum, sigmoid sinus depression
Squamous part
Basilar part
Anterior foramen magnum and includes the clivus of the occipital bone,
jugular foramen
Condylar parts
Lateral borders of foramen magnum and occipital condyles, jugular
foramen
Foramen
magnum
Squamous part
Zygomatic process of the temporal bone
Petrous part
Petrous part houses inner ear
Mastoid part
Mastoid process and air cells
Tympanic
External auditory meatus
Styloid process
Common Incidental Findings
Finding
Jugular foramen size
variations
EAC (external auditory canal)
cerumen impaction
How it presents
Asymmetrical jugular foramen
Views best visualized on
Axial
Radiopaque mass(es) in the external
auditory canal
Axial
Coronal
Sagittal
Orbit
Bones that create this region
Frontal
Key Anatomy
Supra-orbital notch
Other
Superior aspect of orbital rim
Lacrimal
Lamina papyracea
Medial border posterior to maxilla
Maxilla
Inferior and medial aspects of orbital rim
Ethmoid
Medial border posterior to lacrimal
Zygomatic
Inferior and lateral aspects of orbital rim
Sphenoid
Posterior aspect
Common Incidental Findings
Finding
Trochlear apparatus
calcifications
How it presents
Radiopaque U shaped area near
supero-medial aspect of orbital
contents
Views best visualized on
Axial
Coronal
Brain
Brain part
Anterior (anterior cranial fossa)
Middle (middle cranial fossa)
Borders
Frontal bone
Ethmoid bone
Lesser wings of sphenoid
bone
Greater wings of sphenoid
Temporal bone
Posterior (posterior cranial
fossa)
Parietal bone
Occipital bone
Temporal bone
Other
Falx cerebri
Cavernous sinus (internal carotid
artery)
Petroclinoid ligament
Interclinoid ligament
Superior aspect of petrous portion
Pineal gland
Vertebral artery
Choroid plexus
Posterior aspect of petrous portion
Parietal bone
Common Incidental Findings
Finding
Cavernous carotid artery
calcifications
Pineal gland calcification
How it presents
Curved / Linear radiopaque entities
lateral to sphenoid sinus
Views best visualized on
Axial
Coronal
Radiopaque mass in midline at level
just superior to the posterior clinoid
process
Axial
Coronal
Sagittal
Cervical Vertebrae
Cervical Vertebrae
C1 (atlas)
C2 (axis)
C3 to C6
Common Incidental Findings
Finding
Degenerative Joint Disease
Accessory ossicle formation
Key Anatomy
Anterior arch
Posterior arch
Foramen transversarium
Body (odontoid process)
Transverse process (2)
Lamina (2)
Spinous process
Foramen transversarium
Body
Transverse process (2)
Lamina (2)
Spinous process
Other
Posterior ponticle
How it presents
Asymmetrical joint space narrowing
Osteophyte formation
Subchondral cyst formation
Bony erosions
Facet hypertrophy
Views best visualized on
Sagittal
Axial
Coronal
Radiopaque mass(es) superior to dens
Sagittal
Soft Tissues
Soft Tissues part
Prevertebral soft tissue
Key Anatomy / Location
Anterior to cervical vertebrae
Other
Floor of mouth / tonsillar region
Everywhere else
Common Incidental Findings
Finding
Tonsiliths
Hyoid
Carotid artery
How it presents
Radiopaque mass(es) lateral to airway
Views best visualized on
Axial
Coronal
Sialoliths
Radiopaque mass medial to body of
mandible
Axial
Coronal
Carotid artery calcification
Curved / Linear radiopaque entities
antero-lateral to C3/C4
Axial
Coronal
Sagittal
Jaws
Bones
Maxilla
Mandible
Common Incidental Findings
Finding
Degenerative joint disease
(TMJ)
Focal idiopathic
osteosclerosis
Key Anatomy
Alveolar process
Other
Mandibular canal
Mental foramen
Condyle
Coronoid process
How it presents
Asymmetrical joint space narrowing
Osteophyte formation
Subchondral cyst formation
Bony erosions
Views best visualized on
Rotated sagittal cross-sectional
Rotated coronal cross-sectional
Sagittal
Coronal
Radiopaque area with radiopacity of
cortical bone
Axial
Coronal
Sagittal
Cone Beam Computed Tomography (CBCT) Radiology Report
Indication:
Date of Imaging:
Protocol: A (( )) cone beam CT dataset of the [anterior half of the skull and cervical vertebrae] [maxilla] [mandible] was
acquired and reconstructed. The resultant axial, coronal, sagittal, panoramic and orthoradial reconstructions were
examined.
Teeth/Jaws:
Inflammation
Impactions
Fractures
Foreign bodies
TMJ:
Morphology
Degenerative joint changes
Paranasal Sinuses:
Bony borders
Soft tissue thickening/opacification
Nasal Cavity:
Bony borders
Ostiomeatal units
Concha
Airway:
Airway patent
Adenoidal hyperplasia
Cranial Skull Base:
Bony borders
Canals and foramina
Orbit:
Bony borders
Calcifications
Pathosis
Morphology
Foreign bodies
Nasal septum
Brain:
Calcifications
Cervical
Morphology
Prevertebral soft tissue width
Soft Tissues:
Calcifications
Interpretation/Impression:
Degenerative joint changes
Foreign bodies evident
Ossifications/calcifications
Cone Beam Computed Tomography (CBCT) Radiology Report
Indication:
Date of Imaging:
Protocol: A (( )) cone beam CT dataset of the [anterior half of the skull and cervical vertebrae] [maxilla] [mandible] was
acquired and reconstructed. The resultant axial, coronal, sagittal, panoramic and orthoradial reconstructions were
examined.
Teeth:
Jaws:
Paranasal Sinuses:
Nasal Cavity:
Airway:
Cranial Skull Base:
Orbit:
Brain:
Cervical Vertebrae:
Soft Tissues:
Interpretation / Impression:
Self-test
1. Reviewing a patient’s medical history and dental history along with performing an oral exam is recommended
prior to prescribing/ordering a CBCT.
T/F
2. Which of the following is a common incidental finding in the nasal cavity?
a. Antrolith
b. Pineal gland calcification
c. Concha bullosa
d. Focal idiopathic osteosclerosis
3. Degenerative joint disease changes in the cervical vertebrae include: asymmetrical joint space narrowing,
osteophyte formation, bony erosions, facet hypertrophy and subchondral cyst formation.
T/F
4. Degenerative joint disease changes in the temporomandibular joints include: asymmetrical joint space
narrowing, osteophyte formation, bony erosions, facet hypertrophy and subchondral cyst formation.
T/F
5. Which of the following cannot operate a CBCT unit to capture scans in the state of Oregon?
a. Dental student
b. Licensed dentist
c. Dental assistant with CDA
d. Licensed hygienist
6. When creating a CBCT report you only need to comment on the area of concern.
T/F
Answer key
1.
2.
3.
4.
5.
6.
T
C
T
F
A
F